Another argument is this: The (wrong) graph has been drawn with 12 cycles, based on approximately 12 lunar months per year. But the result is obviously not to

Another argument is this: The (wrong) graph has been drawn with 12 cycles, based on approximately 12 lunar months per year. But the result is obviously not to scale. If you try to draw it to scale, the truth jumps out at you; it can't have this form.